The invention relates to a seat belt system with a belt tensioner.
A three-point seat belt is secured to a vehicle at three anchoring points when the seat belt is in a fastened condition. Conventionally these anchoring points comprise an end fitting by which the end of the belt webbing is secured to the vehicle body. A belt lock into which an insertion tab is guided movably on the belt webbing is inserted with locking on fastening the belt. An upper anchoring point is located at, or above, shoulder height for the vehicle occupant, for example a belt guide through which the belt webbing coming from the chest of the vehicle occupant is guided to the winding shaft of a automatic seat belt retractor. In the rear seats or rear benches or seat belt systems integrated within the seat, the belt guide located at, or above, shoulder height and the automatic seat belt retractor may be provided in one structural unit.
EP 0 778 182 A2 teaches, on an end fitting by which an end of the seat belt webbing is secured to the vehicle, a belt tensioner which is a pyrotechnically drivable winding shaft and which exerts a tightening retraction movement or a tensioning movement on the seat belt in a crash.
EP 1 034 990 A2 teaches a belt tensioner in which the tensioning movement is transmitted to the belt webbing with the aid of a push rod. When the known tensioning drive is installed additional belt webbing is required to form a deflection loop which is laid around a deflection face provided at the push rod end.
There is provided in accordance with the present invention a seat belt system comprising: belt webbing; an end fitting by which an end of the belt webbing is secured to a vehicle; a belt tensioner that acts with a pulling eyebolt through which the belt webbing is guided by a webbing guide in the vicinity of the end fitting to transmit a tensioning movement to the belt webbing, wherein the pulling eyebolt has a substantially straight pulling rod by which a pulling movement generated by the tensioning drive is transmitted to the belt webbing during tensioning and during tensioning the pulling rod acts as a webbing deflection rod for the belt webbing guided through the webbing guide; and the webbing guide has two deflection points about which the belt webbing is guided during tensioning and the pulling rod acts on a section of the belt webbing guided between these two deflection points.